You have a very odd view of rights. It's /within their means/ as a producer to require email to view their content. Just because you can do something doesn't make it your right to do something. Doesn't make it wrong to do it either, but that's god damn miles from a right.
In addition, just because you can do something doesn't mean you should, and it's within my means to assert that anyone who asks for my contact information but doesn't know me personally /definitely/ wants to spam me, there's no other reason for them to ask for that information.
Being polite, spamming is rude. Being rude, people who send or enable spam are worthless scum. I have no time for anyone who chooses willfully to be part of that cycle.
My freedom to express that opinion actually /is/ a right[1].
When I enter my email address and click the button, the form expands to add new fields including first name, last name, phone number, and company name. The button still says "Download now", and I don't have the report in my email. So it seems like I just got tricked into providing my email address without getting the report in return.
This Google search finds downloadable mirrors of the report: "2016 State of DevOps Report filetype:pdf"